Nice article. Not everything is an expression in rust as the author mentioned though.
For example all Rust's loops are expressions. This isn't very useful in many cases, but breaking an ordinary loop can yield a value, so e.g. you can loop checking all the integers until you find one you like, and then return it as the value of the loop. Nice.
Coming from python, i feel doing something like this:
let x = for v in iter {
if cond(v) {
break v;
}
} else {
default_v
}
In your example code, I see there's an else clause on the for loop which is presumably special syntax so as to provide the value if it doesn't break, but that feels pretty clumsy to me and I'm not sure there are many cases where it's more readable than what I'd do now.
If I could see a nice way to do it without such clumsy special syntax, I'd favour this, but with the else syntax (or some equivalent) it feels like it doesn't pull its weight.